Typically, as used in a storage rack arranged for gravitational flow of load-bearing pallets, a roller track having a slight inclination (e.g. 3.degree.) relative to a horizontal plane comprises two walls disposed in parallel relation to each other, a longitudinal array of freely rotatable rollers journalled between the walls in such manner that the rollers extend upwardly from a space therebetween, and an elongate stop having a hooked end. The elongate stop is mounted to and between the walls, at a lower end of the roller track, in such manner that the hooked end points upwardly. The elongate stop may be so oriented as to impart frictional drag tending to slow a load-bearing pallet approaching the hooked end. In such a storage rack, in each lane on each level, it is conventional to employ two roller tracks disposed in parallel relation to each other and at a slight inclination relative to a horizontal plane. Such storage racks are available commercially from Unarco Material Handling (a unit of UNR Industries, Inc.) of Chicago, Ill.
Commonly, the elongate stop is made from cast iron, which has sufficient strength to withstand repeated impacts of load-bearing pallets slamming into the hooked end. A disadvantage of cast iron is that cast iron is not sufficiently shock-absorbing. Consequently, when a pallet bearing a load slams into the hooked end of such a stop made from cast iron, there are tendencies for parts of the load to shift excessively or to fall from the pallet. Aluminum, which is less expensive to fabricate into such a stop, has been tried but has been found not to be sufficiently shock-absorbing and to be unduly susceptible to breakage. Various polymeric materials, which could have been more shock-absorbing, have been tried but have been found to be unduly susceptible to breakage.
Thus, there has been a need for an improved stop for a roller track, as discussed above.